This 1968 Mullard circuit detects fire by smoke using LDR-type sensors. The circuit makes use of transistors of the time that admit equivalents.
The circuit is from the 1990 Motorola Linear Databook. The circuit can be implemented with other...
Found in Texas Instruments documentation from the 1980s, this circuit applies to digital signal...
This circuit was found in a 1980s US publication. There may be some difficulty in obtaining the...